A Perfect 10 | Soft Synths

In less than 13 years, virtual synthesizers have completely changed the way musicians interact with electronic sound sources. EM reviewed just one software instrument (Seer Systems Reality) in 1997, and just one more (Propellerhead ReBirth RB-338) in 1998. By 2000, however, EM''s first soft-synth roundup covered 19 products and noted that more were available.

Now it''s practically impossible to keep count. What a difference a decade makes! In 2010, increasingly powerful software continues to challenge synthesizer hardware. Now that almost every classic synth has been modeled, computer-packing musicians have an ample selection of virtual instruments. It''s been a few years since EM published a soft-synth roundup, so it''s finally time to investigate the latest crop.

For this article, I limited my selection to six synths and one four-synth bundle, each from a different manufacturer. All are cross-platform, and all run as plug-ins in popular DAWs without DSP host hardware. Only three emulate specific hardware synths; most others draw their inspiration from vintage hardware by modeling circuitry in a more general fashion.

FabFilter Twin 2.2 ($174, download, AU/RTAS/VST)Twin 2 is a virtual analog synth that supplies three audio oscillators with independent panning, four self-resonating multimode filters, and (dare I say it?) unlimited modulation capabilities. Likewise, undo and redo are unlimited, and the plug-in comes with more than 1,600 varied presets, most of them excellent (see Web Clip 1). Twin 2''s icon-based GUI is a snap to maneuver (see Fig. 1). If you ever need help, holding your cursor over any parameter quickly summons a descriptive popup.

The two main filters borrow their 11 types from one of my favorite filtering plug-ins, FabFilter Volcano 2. Clicking on the filter icon reveals additional controls. You adjust filter cutoff and resonance peak by simply clicking and dragging on an image of the filter curve; that''s more intuitive than adjusting knobs, which are also provided, because you more immediately grasp the one-to-one relationship between what you see and what you hear. Holding the Command key (Control key in Windows) as you drag changes the filter panning or response type (lowpass, highpass, or bandpass).

Likewise, clicking and dragging on an oscillator icon changes oscillator octave and detuning, and Command-clicking and dragging changes sync depth and waveshape (four basic waveforms, plus pink and white noise). Clicking on an oscillator icon reveals knobs for the same parameters, as well as pulse width. You also get right and left delay processors with similar click-and-drag functionality and an additional pair of multimode filters. Maximum delay time is a generous 5 seconds, long enough to build Frippertronics-type loops.

Twin 2''s modulation capabilities are most impressive. A scrolling bar lets you slide the GUI''s contents to the left and right to see all the mod sections, which include X/Y controllers, 6-stage envelopes, MIDI routings, and more. Anytime you need an extra modulator, just add it.

FXpansion DCAM Synth Squad 1.0.1.2 ($249, download or boxed, AU/RTAS/VST/standalone)Synth Squad is a collection of three analog-modeling soft synths—Strobe, Amber, and Cypher—bundled with a fourth synth called Fusor that hosts any combination of the other three. Although Strobe is a traditional synth firmly rooted in familiar territory, Cypher and Amber offer some fresh approaches to computer-based synthesis. Even the most experienced synthesist could learn new techniques and create some original timbres in the process.

Synth Squad''s synths have many commonalities, most obviously in their GUIs. All offer an arpeggiator and glide, and you can stack polyphonic voices to create fat unison sounds. Each has a browser for searching presets, filtering the results, and aurally previewing any sound before loading it. Though some of the mod routings are hardwired (virtually, of course), all these plug-ins share a modulation scheme called TransMod, which provides eight slots for routing one source to several destinations while allowing one source to scale the mod depth of several others. A Visualizer Scope near the GUI''s center displays the waveform most appropriate for the onscreen control beneath your mouse cursor. For example, if your cursor is over the Oscillator section, you''ll see the audio waveform, and if it''s over the Filter section, you''ll see the response curve.

Strobe. Strobe is simple and straightforward, designed for ease of use and quick access to subtractive-synthesis parameters. Even though it has just one main oscillator, you can stack multiple voices in unison and detune them, and tune the 4-waveform sub-oscillator as much as three octaves lower. Strobe''s flexible filter offers 22 modes, including 1, 2, and 4-pole lowpass, highpass, bandpass, notch, and peak filter types and various combinations. Strobe also has one LFO, two ADSRs, and a ramp generator serving as mod sources, but it has no effects processing.

Amber. Emulating classic string machines is Amber''s domain, and it takes a novel approach. Rather than simply playing samples of the ARP Omni, Elka Rhapsody, and the like, Amber models their paraphonic sound generation, which traditionally relied on 12 top-octave frequency dividers. Vox Continental and Farfisa combo organs used the same technique, but surprisingly, you won''t find simulations of those in Amber''s patch collection (see Web Clip 2). Consequently, some of the parameters are slightly out of the ordinary.

Amber has two sections, Synth and Ensemble, which are layered to produce a blend of their sounds. In addition to each section having its own 1-pole filter, Synth has a resonant multimode filter, and Ensemble has a tunable 4-band formant filter and a versatile chorus effect. Whereas Synth has an ADSR envelope, Ensemble has an attack-release envelope with a button that disables sustain, effectively turning release into an initial decay. A second ADSR, a ramp generator, and eight TransMod slots are available as modulation sources for both sections.

Cypher. With more of just about everything, Cypher specializes in analog-style FM (unlike Yamaha''s DX-style, multi-oscillator FM) and traditional subtractive synthesis (see Fig. 2). It also functions as an effects processor for external audio even though, like Strobe, it has no onboard effects of its own. Because it''s meant to handle FM and other forms of audio-rate modulation, it furnishes a few parameters you wouldn''t see on a typical analog synth, including controls for Scale, which tunes the oscillators and filters in harmonic ratios rather than semitones—especially useful for FM and wave-modulation programming.

Although Cypher''s three identical oscillators are more complex than you''d normally find, they produce only the four standard analog waveforms, but you can continuously modulate their waveshapes using any TransMod source. You can adjust oscillator detuning by fractions of a beat and then use the beat frequency as a mod source—a technique I''ve never seen before. You can also trigger modulation with MIDI note-on or note-off messages.

Cypher''s dual multimode filters have both shared and independent parameter controls and can be arranged in series or parallel. In addition, you get two LFOs, three ADSRs, a ramp generator, and—another innovative touch—sample-and-hold at audio frequencies. With so many programming resources, Cypher delivers a sonic playground like no other. Dozens of factory patches cover all the bases, with an emphasis on electronic sounds rather than traditional instrument simulations (see Web Clip 3).

Fusor. With three slots for inserting Strobe, Amber, or Cypher, Fusor lets you layer and split any combination. Its effects suite, step sequencer, and extra mod sources add considerably to Synth Squad''s power (see Web Clip 4). Additional mod sources include four LFOs and four envelope followers. Eight macro controls let you modulate practically any parameter in real time using MIDI controllers.

Each slot accommodates three insert effects, and you can apply three effects from the same list to the master bus. There are 27 effects choices including 4-band EQ, 4-band distortion and comb filtering, an SSL-style bus compressor, a granular freeze effect, and a selection of reverbs on loan from Overloud Breverb.

Any of Synth Squad''s synths are well worth having. Amber and Cypher open the door to synthesis techniques that stray from the mainstream. Fusor lets you combine all of them in a single powerful plug-in with more modulation routings than you''ll know what to do with.

FIG. 3: Scanned Synth Pro 2, from Humanoid Sound Systems, combines physical modeling and wavetable synthesis using a technique developed in the late ''90s.

Humanoid Sound Systems Scanned Synth Pro 2.0.11 (donationware, download, AU/VST/standalone in Windows only) In the late ''90s, a pioneering team of scientists at Interval Research came up with a new sound-generating technique that combines wavetable synthesis and physical modeling. Scanned synthesis lets you continuously alter spectra by changing a modeled object''s physical characteristics in real time.

Scanned Synth Pro costs whatever you want to pay for it, and it sounds amazing; that''s a rare combination. Its patch collection supplies 111 presets that run the gamut from simple, Bassic bass and Chainsaw lead, to complex, Cheap Alien FX and Stoned Out Cyborgs. The programming depth is impressive, and lots of patches respond to aftertouch and other real-time gestures. Many factory sounds are variations on analog classics but with more animation than usual (see Web Clip 5). You get 144 additional slots for storing your own patches, though you''ll likely be dealing with a few parameters you''ve never seen before.

User parameters are split into four pages—Synthesis, Modulation, Effects, and Master—that you access with tabs (see Fig. 3). The five main parameters on the Synthesis page are Mass, Hammer, Update Rate, Centre Force Scale, and a Connection Matrix. All of these parameters manipulate a virtual string whose nodes are connected by springs being struck by a hammer shaped by waveforms. Right-clicking on any parameter summons a brief explanation, but the quickest way to create your own sounds is to click on the Randomizer switch.

The Modulation page puts you in more familiar territory with two LFOs, two ADSRs, and an envelope follower that accepts audio signals. The Effects page—in addition to reverb, echo, flanger, and chorus—furnishes a master filter and a polyphonic filter for altering voice timbres individually. On the Master page, in addition to controls you might expect, you''ll find the Panic Group''s Psycho and Danger switches. Psycho adds random nastiness, and Danger delivers even more serious distortion.

FIG. 4: Image Line Sawer accurately models the Formanta Polivoks, the most popular synthesizer you may have never heard of.

Image Line Sawer 1.1.2 ($99, download, AU/VST/FL Studio/ standalone)Sawer emulates a Soviet-made synthesizer, the 2-voice analog Formanta Polivoks. In the ''80s, the Polivoks was so popular in the Eastern Bloc that it''s estimated about 100,000 were built.

For the most part, the monotimbral Sawer adheres to standard subtractive architecture with two oscillators, one multimode filter, one LFO, two ADSRs, and glide (see Fig. 4). The effects section furnishes chorus, phaser, a panning delay, and a springy reverb that actually degrades the sound. Sawer also has an arpeggiator with up, down, and random modes.

The main oscillator produces only sawtooth waves. Most oscillator controls affect only the Sub-Saw oscillator, which generates either sawtooth or square waves. You can lock the main oscillator to an unseen sync oscillator and then shift the sync oscillator''s pitch a maximum of 24 semitones higher or lower, but only in fifths and octaves. Engaging the unison function layers as many as eight voices, subject to Sawer''s 24-voice polyphonic limit.

The filter offers highpass, bandpass, and 2- and 4-pole lowpass responses. It has an especially meaty sound at high-resonance settings. The filter''s envelope generator is reassignable to modulate the sync oscillator''s frequency, the main oscillator''s frequency, or the Sub-Saw''s phase. Like the Polivoks, Sawer depends heavily on oscillator-sync modulation for its characteristic sound (see Web Clip 6).

The LFO has a dedicated 2-stage envelope generator and offers four invertible waveshapes. You can route its signal to any one of seven destinations, including oscillator sync. The MIDI Modulation Matrix conveniently displays the routing of any real-time controllers and allows you to specify your own mod routings.

Sawer''s presets are divided into nine banks of 36 each, but only one bank is included. You can download the entire collection from Image Line for $9.

Rob Papen Predator 1.5.5 ($179 , download, AU/RTAS/VST) From Dutch synthesist Rob Papen, Predator is a 16-voice subtractive synthesizer with three oscillators, two filters, four 5-stage envelope generators, eight modulation routings, and a generous assortment of effects (see Fig. 5). The oscillators let you choose from 128 waveforms—modeled analog and computer-generated spectra—and handle FM and ring modulation. Engaging the Spread parameter allows each oscillator to generate the sound of additional detuned oscillators. Each has its own LFO (hardwired to modulate pulse width) and a square-wave sub-oscillator.

In addition to lowpass, highpass, bandpass, and notch responses at various slopes, Predator''s stereo filter has comb and Vox settings; the latter produces vowel-like formants. A second stereo filter has eight lowpass and highpass settings and a split mode that shares duties with the main filter. The main filter has its own LFO and 5-stage envelope, and another 5-stage envelope controls amplitude. You can route two assignable envelopes and two assignable LFOs to any of 66 destinations and control their depth with whatever source you choose.

One of Predator''s standout features is preset morphing, which allows you to select two presets from the same bank and then generate a new preset combining their characteristics. Another is the Variation knob, which generates four alternatives to the currently selected patch. You can use Predator''s comprehensive 16-step arpeggiator as a step sequencer or modulation source. The 24 effects types include wave-shaping, amp simulation, and wah-wah delay.

With names such as Predator Dance, Trance and PsyTrance, and HipHop DirtySouth, most of the included banks are obviously designed for electronic dance music (see Web Clip 7). However, you also get three Classic Synth banks, two Ambient banks, and four All Basses banks (among others), and optional banks are available from Rob Papen and third parties.

Waldorf Largo 1.5 ($249, download or boxed, AU/VST) Waldorf''s penchant for naming synthesizers after James Bond characters is evident in Largo, a multitimbral plug-in that emulates the company''s Q and Blofeld hardware synths. Four independent parts can be layered or addressed via separate MIDI channels, and you can send them to separate outputs for a surround mix. Although the feature set is comprehensive, Largo''s layout is clear and logical with lots of thoughtful touches (see Fig. 6).

Largo''s three oscillators, which model classic analog waveforms, can be turned on and off as needed. Two of them also generate 68 wavetables and are paired with square-wave suboscillators for added fat. Controls for FM, ring mod, and wave modulation are on hand, and the noise generator''s bipolar Colour knob controls continuously variable noise filtering. To thicken the sound, you can trigger as many as eight voices per note.

Two identical filters offer lowpass, bandpass, highpass, and notch responses at either 12dB or 24dB per octave, with two comb filter settings to boot. Pan the filters independently and route them in series or parallel. A choice of eight Drive Curves lets you dial in just the right saturation character. Freely assign the four envelopes using Largo''s 16-slot modulation matrix; they offer ADSR, one-shot, or loop-optional 6-stage modes. Each of three LFOs displays an image of its selected waveform, complete with delay at the front end and fade at the back.

Largo''s flexible 16-step arpeggiator has slots for 16 patterns (one user-defined), and you can apply two effects to each layer or part. Effects include flanger, reverb, and four other types, and you also get 4-band parametric EQ. Largo''s Browse page lists more than 700 fat, useful, and occasionally stunning timbres to suit almost any occasion (see Web Clip 8).

FIG. 7: Forty years after EMS launched the VCS 3, XILS-lab improved upon it with XILS 3, a faithful emulation that adds a step sequencer, two extra envelope generators, sample and hold, and more.

XILS-lab XILS 3 1.1.1 ($199, download, AU/RTAS/VST) One of the earliest popular synthesizers was the VCS 3, a compact analog monosynth from London-based EMS (Electronic Music Studios). Its odd form factor, pin-matrix patching system, and characteristic sound endeared it to many musicians, in no small part thanks to its appearance on records by The Who, Pink Floyd, and Brian Eno.

XILS 3 is an 18-voice polyphonic plug-in that faithfully re-creates the VCS 3 and extends its functionality. The GUI''s right side looks almost exactly like the VCS 3 laid flat, with rows of knobs, the distinctive patch matrix, a joystick, and a VU meter that indicates input level (see Fig. 7). Clicking on intersections within the matrix connects any of 16 audio or control sources to any of 16 destinations. Nothing is hardwired, so matrix connections are necessary to produce any sounds.

Like the original, XILS 3 has two oscillators that generate square and triangle waves and another that generates sine and sawtooth waves. Its noise generator offers continuously variable color, and the resonant lowpass filter has a switch for 2, 3, or 4-pole response. Additionally, XILS 3 has an out-of-the-ordinary trapezoid envelope shaper, ring modulation, and a simulated spring reverb you can place anywhere in the signal path.

On the GUI''s left side, the bottom half contains an onscreen keyboard and controls for a 128-step sequencer. What appears in the top half depends on which of seven tabs you select. For example, selecting the Matrix tab displays three extra matrices for additional connections. Clicking on Input reveals the Transient, Gate, Envelope Follower, and Pitch Tracker controls for processing external inputs. You also get two effects: chorus and a panning delay.

Many of XILS 3''s large collection of patches explore experimental realms, and many have a decidedly retro vibe. XILS 3 sounds more realistically analog than most soft synths I''ve heard (see Web Clip 9). Thanks to its nonstandard features, it''s a wonderful medium for discovering new territory with traditional analog synthesis.